Artificial Kidney Designed

Around 1980, an artificial kidney machine was built that incorporated many of the principles on which the new technology relies, according to the scientists. But that machine, while portable, was not wearable. The new technology, the peritoneal-based artificial kidney, would allow patients to go about their regular business while undergoing dialysis.

"What's really new about it is the patient's freedom," Martin Roberts, one of the designers, says. "The next important thing is that because it's working all the time instead of intermittently, you can do a much better job of treating the patient. So we expect the patient to feel better and live longer."

Kidneys remove metabolic wastes from the body and regulate fluid volume and distribution on a continuous, around-the-clock basis. With traditional hemodialysis, patients are hooked up to a machine for four hours, three times a week. Their blood is filtered through the machine to remove toxins and is then pumped back into the body.

What hemodialysis or standard peritoneal-based dialysis cannot do, however, is provide cleansing and fluid balance on a continuous basis; therefore, toxin levels and fluid volume tend to fluctuate, causing "shocks" to the patient's system, the scientists explain. In addition, hemodialysis uses anticoagulants to prevent the blood circulating outside the body from clotting. But this, too, can cause complications, the researchers say.

The artificial kidney, on the other hand, would function continuously, as natural kidneys do. And because it does not involve blood circulation outside the body, it is "bloodless". It also regenerates and reuses fluid and protein components in the spent dialysate - the fluid that has abstracted toxins from the patient's blood and which is discarded in current practice - making it waterless and minimising or eliminating protein loss.